The Nature and Development of HIV/AIDS

Issue 7, Number 2
October 1996

by Colette Vidal

  • The Human Immunodeficiency Virus
  • The Stages of HIV Infection
  • The Transmission of HIV
  • Sexual Transmission
  • Tests for HIV Infection
  • Psycho-social Aspects of Testing for HIV
  • Meaning of a Positive Test
  • Bibliography


    The Human Immunodeficiency Virus

    A virus is a very small organism which can only be seen through a microscope. Unlike other germs, a virus can only reproduce itself by entering a living cell and taking over some of that cell's material.

    White blood cells called macrophages (1) and lymphocytes play an important role in HIV infection. When HIV enters the body, it binds itself to the lymphocytes, a type of white cells also called "helper cells" because they "instruct" other cells to fight off "foreign" intruders such as germs. HIV can enter T4 cells because they have what is called a CD4 receptor which matches the virus' key. Once HIV has entered these cells, its genetic material, RNA (ribonucleic acid), must be changed to match the cells' DNA (deoxyribonucleic acid). This is achieved with the help of enzymes. The invaded cells then begin to reproduce the virus, making hundreds of copies of HIV, which when ready burst out of the cells into the blood and lymph of their carrier host. T4 cells die about 24 to 36 hours after being infected with HIV. Although the body is able to replace them, their numbers decrease over time. As these cells are key agents in the immune response to various infections, their depletion eventually causes a serious deficit in normal antibodies, thereby opening the host body to all kinds of opportunistic infections.

    1. This discussion on the HIV development process is based on material from Patterson and Robichaud, Managing Your Health, 1996, p.16-17 and 25.


    The Stages of HIV Infection

    · Window · Asymptomatic Period · Symptomatic Period · AIDS

    The "Window" Period:

    This period refers to the time between the first exposure to HIV and "seroconversion," that is the production of antibodies by the immune system in response to HIV infection. It is only at this point that a blood test will be positive and this may take anywhere from six weeks to six months after the initial infection with HIV. Since there are no obvious symptoms of infection, a person does not know he or she is infected but can nonetheless infect other people.

    The "Asymptomatic" Period:

    During this period, which may last several years, HIV works silently in the carrier host and slowly but surely destroys the T4 cells. There usually are no symptoms or there may be swelling of the lymph nodes (neck and armpits, for example).

    The "Symptomatic" Period:

    As the immune system is weakened by the virus, various symptoms develop. Those can include fever, diarrhea, drenching night sweats, persistent tiredness, weight loss, and several infections.

    Acquired Immune Deficiency Syndrome:

    AIDS is the last stage in HIV infection. At this stage, a person has usually been living with HIV for many years and the immune system is seriously damaged. The onset of AIDS is marked by the emergence of severe "opportunistic" infections which would not develop in an individual with a healthy immune system. These infections are not directly caused by HIV but are the consequences of HIV's weakening of the immune system. Full-blown AIDS is therefore diagnosed by the presence of one or more specific diseases which are caused by organisms common in the environment. Such diseases include:

    Pneumocystis carinii, which causes a severe form of pneumonia and is found in about 50 per cent of AIDS patients (Canada's Blueprint, 1990:9). Women patients, however, tend to "develop bacterial pneumonia before PCP" (AFNATF 1994:11). Persons with AIDS also often develop Kaposi's Sarcoma, a kind of skin cancer, although this is very rare in women patients (Ibid:10).

    Toxoplasmosis, a parasite that infects the brain; cryptosporidium, a protozoan infection that causes diarrhea, Herpes simplex I and II viruses, which cause sores on the lips or genitals that do not heal in the usual seven to fourteen days; Candida Albicans, which causes vaginitis in otherwise healthy women, is sometimes found in the throat and lungs of people with AIDS.

    All the above conditions and several others contribute to an AIDS diagnosis because they are rarely found in people with healthy immune systems (Idem). In most cases, one of these infections will eventually cause the death of the person living with AIDS. There is however, some variation in the severity of symptoms from one individual to another and drugs are now available that can reduce HIV's damage to the immune system and prolong life.



    The Transmission of HIV

    HIV can be transmitted from an infected person to someone else when there is an exchange of blood, semen or vaginal secretions. In addition, a baby born to an HIV-positive mother has a 14 to 25 per cent chance of being infected (The College of Family Physicians of Canada, 1995:23).

    Requirements for Transmission (AFNATF:13).

    The virus has to be present in a person's body in sufficient concentration in order to be transmitted.
    The virus must get into the other person's bloodstream to cause infection.

    "The behaviors that can result in HIV transmission are certain sexual activities, sharing injection drug needles or receiving infected blood or certain blood products (prior to the screening of blood and blood products implemented in 1985)" (Idem).

    Sexual Transmission

    Unprotected sexual intercourse with same sex or with other sex infected partner, whether anal or vaginal.
    Oral sex (fellatio - cunnilingus), with an infected person.
    Donor insemination with infected semen although most semen is now screened for HIV.

    Non-sexual Transmission

    Sharing injection drug needles with an infected person. The blood of an infected person can in this way pass directly into the other person's bloodstream. This is probably the most efficient way to transmit HIV. One should also be wary of tattooing needles which may present a risk of infection if they are not sterile.

    Receiving blood transfusions or blood products coming from infected donors. This risk is currently minimized as the Red Cross has been screening all blood donations since November 1995. The currently detected AIDS cases related to this mode of transmission were more likely transmitted by blood received before this date.

    Prenatal transmission from an infected mother to her child either prior to birth at birth, or through breastfeeding, although breastmilk does not contain high concentrations of HIV.
    Needlestick exposures to HIV in the occupational setting can, in some cases, result in HIV infection. However, this risk is well known at 0.3 per cent or 3 per 1,000.

    It must be pointed out that HIV cannot be transmitted through saliva, tears, insect bites, casual contact with infected persons or sharing eating utensils, pools or hot tubs with them. Kissing a person with HIV/AIDS is not a risky activity. "Wet kissing" however, could be problematic should one have a cut or sore in the mouth allowing for the exchange of blood from the infected person. But there is no evidence whatsoever to show that one can contract HIV through saliva. The concentration of HIV in saliva is so minute that one would "have to inject over a quart of it into one's veins in order to become infected" (Ibid:18).

    Tests for HIV Infection 

    There are two kinds of tests used to look for antibodies to HIV. The ELISA test, which stands for "enzyme-linked immunosorbent assay," is done first (Patterson and Robichaud:23). If the ELISA is positive, a second test, the Western Blot, is performed to confirm the results. If both tests are positive, it means that antibodies to HIV are being produced, indicating the presence of HIV in the body. Viral load tests can also be performed. These show the actual amount of HIV present in the blood. They can show whether infection has occurred even if the immune system has not produced any antibodies (Idem).

    The T4 percentage test is used to determine the percentage of T4 cells compared to the total number of lymphocytes in the blood. This, as well as absolute T4 cell counts, gives an indication of the state of the immune system. If the number of T4 cells is low, it may be necessary to start taking action in order to delay further deterioration of the immune system.

    It is worth remembering that a person may test negative during the "window period." A second test should be performed at a later date to allow for the production of antibodies to HIV.

    Psycho-social Aspects of Testing for HIV

    The patient must be made aware of the testing procedures and the potential benefits of testing, but also of the risks and consequences of being found seropositive (testing positive for HIV). He or she must give informed consent before being tested. The confidentiality issue must be discussed regarding the test results and the three possible options (AFNATF:84).

    Nominal testing: The name of the patient and Medicare number are put on the test requisition. In this case, positive results are submitted to the Department of Health. This can lead to identification of the infected persons.

    Non-nominal testing: A code disguises the patient's name on the testing requisition and is known only to physician and patient. This offers a better protection of confidentiality.

    Anonymous testing: The patient's identity remains undisclosed and the sample is only identified by a code name and a number given by the clinic's staff. Some patients prefer this third option to avoid possible breaches of confidentiality but this type of testing is only available at certain special clinics.

    In the case of a positive test, the patient has an ethical obligation to inform any sexual or drug-using partner(s) that they have been exposed to HIV. If the patient refuses to do so, the physician is obligated to inform such partners, but only after informing the patient that this will be done.

    Meaning of a Positive Test

    Testing positive means that HIV has entered the body and therefore the whole process involving the deterioration of the immune system has begun. However, to prevent or at least delay the onset of AIDS or HIV-related symptoms, one should (Ibid:85):

    • seek prompt medical attention
    • get plenty of rest and exercise
    • eat a well-balanced diet
    • avoid drug abuse, including alcohol; avoid stress and think positively.
    • Test results should never be communicated by phone or mail and seropositive patients should be provided with post-test counseling to help them with the difficult task of coming to accept the result and dealing with the stress and anxiety involved.



    1. Atlantic First Nations AIDS Task Force, (AFNATS) Healing our Nation, Resource Manual, 1994.
    2. Brandling-Bennett, David, "The Impact of AIDS in the 1990's," International Law and Politics, Vol. 23, 1991:989-999.
    3. Challem, Jack, "Glimmers of Hope: Nutrients Bolster the Immune System of HIV and AIDS Patients;" Health Naturally, August/September 1995:7-10.
    4. Health and Welfare Canada, HIV and AIDS: Canada's Blueprint, Minister of Supply and Services Canada, 1990.
    5. Krause, Dr. Richard, M., "Defining the Metaphor of our troubled age," Canadian AIDS News, Special Insert, Canadian Public Health Association N.D.
    6. Marieb, Elaine, M., Human Anatomy and Physiology, Benjamin Cummings Inc., Redwood, California, 1992.
    7. Patterson, Brent and Francis Robichaud, Managing your Health, a guide for people living with HIV or AIDS, Produced by CATIE, RCITS, and TPWAF, 1996.
    8. Tanner-Spence, Marylin, Together we can stop AIDS, Manitoba AIDS Steering Committee working with First Nations, 1995.
    9. The College of Family Physicians of Canada, A Comprehensive Guide for the Care of Persons with HIV Disease, Module 2: Infants, Children and Youth, Health Canada, 1995.
    copyright © 1997 NIICHRO 05/01/98